Expression of a small (p)ppGpp synthetase, YwaC, in the (p)ppGpp0 mutant of Bacillus subtilis triggers YvyD‐dependent dimerization of ribosome

MicrobiologyOpen

Kazumi Tagami⁴  Hideaki Nanamiya⁵  Yuka Kazo⁴  Marie Maehashi⁴  Shota Suzuki⁴  Eri Namba⁴  Masahiro Hoshiya⁴  Ryo Hanai⁴  Yuzuru Tozawa⁵  Takuya Morimoto¹  Naotake Ogasawara²  Yasushi Kageyama¹  Katsutoshi Ara¹  Katsuya Ozaki¹  Masaki Yoshida³  Haruko Kuroiwa³  Tsuneyoshi Kuroiwa³  Yoshiaki Ohashi⁶ 

[1] Biological Science Laboratories, Kao Corporation, Ichikai, Haga, Tochigi, Japan;Graduate School of Information Science, Nara Institute of Science and Technology, Ikoma, Nara, Japan;Research Information Center for Extremophile, College of Science, Rikkyo University, Tokyo, Japan;Department of Life Science, College of Science, Rikkyo University, Tokyo, Japan;Cell-Free Science and Technology Research Center, Ehime University, Bunkyo-cho, Matsuyama, Japan;Human Metabolome Technologies, Inc., Kakuganji, Tsuruoka, Yamagata, Japan

关键词: Bacillus subtilis;    (p)ppGpp;    (p)ppGpp synthetase;    ribosome dimerization;    stringent response;    YvyD;   

DOI  :  10.1002/mbo3.16

来源: Wiley

【 摘 要 】

Abstract

To elucidate the biological functions of small (p)ppGpp synthetases YjbM and YwaC of Bacillus subtilis, we constructed RIK1059 and RIK1066 strains carrying isopropyl-β-D-thiogalactopyranoside (IPTG) inducible yjbM and ywaC genes, respectively, in the ΔrelA ΔyjbM ΔywaC triple mutant background. While the uninduced and IPTG-induced RIK1059 cells grew similarly in LB medium, the growth of RIK1066 cells was arrested following the addition of IPTG during the early exponential growth phase. Induction of YwaC expression by IPTG also severely decreased the intracellular GTP level and drastically altered the transcriptional profile in RIK1066 cells. Sucrose density gradient centrifugation analysis of the ribosomal fractions prepared from the IPTG-induced RIK1066 cells revealed three peaks corresponding to 30S, 50S, and 70S ribosome particles, and also an extra peak. Electron microscope studies revealed that the extra peak fraction contained dimers of 70S ribosomes, which were similar to the Escherichia coli 100S ribosomes. Proteomic analysis revealed that the 70S dimer contained an extra protein, YvyD, in addition to those found in the 70S ribosome. Accordingly, strain resulting from the disruption of the yvyD gene in the RIK1066 cells was unable to form 70S dimers following IPTG induction, indicating that YvyD is required for the formation of these dimers in B. subtilis.

【 授权许可】

CC BY-NC   
© 2012 The Authors. MicrobiologyOpen published by Blackwell Publishing Ltd.

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